Sound-reproducer for phonographs



J. W. FORDERER.

SOUND REPRODUCEH FOR PHONOGRAPHS. APPLICATION rum APR. 8, 1920.

1,393,10 Patented 00 11, 1921. .2221. 14 5' v w INVENTOR. .229" 5 J W 14; Forder'en PATENT OFFICE.

JOHN w. ronnnnnn, on SAN FRANC1SCO, CALIFORNIA.

SOUND-REPRODUCER FOB PHONOGBAPHS.

Specification of Letters Patent.

Patented Oct. 11, 1921.

Application filed April 8, 1920. Serial No. 372,280.

To all whom it may concern:

Be it known that I, J OHN WESLEY FoRnnnnn, a citizen of the United States, residing at San Francisco, in the county of San Francisco, State of California, have in vented a new and useful Sound-Reproducer for Phonographs, of which the following is a specification, in such full and clear terms as will enable those skilled in the art to construct and use the same.

This invention relates to the reproduction apparatus of a phonograph and its object is to provide an indirect means for transmitting the needle movement to the arm, which is connected to the reproducing diaphragm.

Another object of the invention is to provide means whereby the quality of reproduction may be varied without varying the speed of the rotation of the record as its roughened surfaces pass under the needle. This is accomplished by varying the tension of the diaphragm with an adjusting screw.

Another object of the invention is to provide such connection between the needle carrying arm and diaphragm arm as will eliminate the needle movements in one plane from the diaphragm arm, thereby reducing the mere noise making movement of the latter arm. The result of this is that records that are badly worn and scratched can be played without the disturbing effects usually produced by such records.

Another object of the invention is to provide a resilient means for pressing the needle carrying arm and its strut against the diaphragm arm, thereby enabling the tension on the diaphragm to be nicely regulated.

Other objects of the invention will appear as the description proceeds.

An embodiment of the invention is shown in the accompanying drawings in which the same reference numeral is applied to the same portion throughout, but I am aware that there may be modifications thereof.

Figure 1 is a vertical sectional view through the sound reproducing box and showing the arrangement of the sound reproducing needle and arms.

Fig. 2 is a plan view of the box shown in Fig. 1.

Fig. 3 is a bottom plan view of the box shown in Fig. 1.

Fig. 4 is an elevation of the box looking from the left Fig. 1.

Fig. 5 is a sectional view on an enlarged scale showing the operation of the needle arm adjusting pin.

The numeral 1 indicates the sound reproducing box which has a ferrule 52 for connecting it to the small sound reproducer of the sound reproducing horn, A suitable diaphragm 3 is secured to the sound reproducer box by means of the ring 4, which ring is secured in place by a plurality of small screws 5 and it has a lug 6 at one side, which lug supports the plate 7. The plate 7 has two arms'8 and 9 connected therewith, which arms supply the pivots for the needle holder 10 and the sound reproducing arm 11. The needle holder has an opening at one end to receive the needle 12, which is secured in place by means of suitable thumb screws 13 and at the other end there is a short strut 14 which bears upon the needle holder 10 and upon the sound reproducing arm 11.

The sound reproducing arm is securely connected to the center of the diaphragm 3 and by means of the thumb screw 15, the pressure of the strut 14 upon the arm 11 will be determined and similarly the stress under which said arm places the diaphragm.

In order to provide a resilient pressure of the screw 15 against the needle carrying arm 1O, a short needle 16 provided with a flange 17, is used. This needle rests upon a spiral spring 18 and a separate spiral spring 19 rests upon the opposite side of the flange 17 of the spring 18 and bears on the end of the screw 15, so that by tightening or loosening the screw 15, the pressure of the needle 16 of the arm 10 is adjusted.

In operation the apparatus is set up so that the strut 14 will be permanently secured in place and the quality of the tone is varied to suit, by means of the adjusting screw 15.

What I claim is as follows, but various modifications may be made in the construc tion shown in the drawings and above particularly described form, within the purview of my invention.

1. A sound reproducer for phonographs comprising a sound box, a diaphragm connected thereto, a pair of lugs carried by the box, an arm pivotally connected to the said lugs and connected to the center of the diaphragm at its other end, a needle carrying arm pivotallymounted in said lugs, a strut between one end of the needle carrying arm a strut between the needle carrying arm 10 and diaphragm arm, a spring operated post bearing upon the ne edle carrying arm and a screw for adjusting the pressure of said post upon the needle carrying arm.

In testimony whereof I have hereunto set 15 my hand March A. D. 1920.

JOHN W. F ORDERER. 

